Under what conditions will air brakes automatically extend during a rejected takeoff and landing?

Air brakes on the Dassault Falcon 2000LXS are designed to enhance the deceleration of the aircraft during a rejected takeoff or landing scenario. The correct condition for their automatic extension is when both the left-hand (LH) and right-hand (RH) landing gears are depressed, coupled with a reduction in thrust by retarding the thrust levers.

This design is based on the aircraft's operational needs during landing and rejected takeoff scenarios, where quick deceleration is crucial for safety. The activation of the air brakes upon landing gear contact ensures that the aircraft begins to slow down effectively and can help manage the aircraft's speed in critical phases. Retarding the thrust levers signals that the pilots are reducing engine power, further supporting the need for immediate deceleration.

In contrast, if the AUTO EXT pushbutton is in manual, the air brakes would not automatically deploy, thus negating this condition. When thrust levers are at full power, the plane is typically in the acceleration phase rather than requiring air brakes. Lastly, speed exceeding 200 knots is an irrelevant condition here, as the air brakes need to activate based on landing gear and throttle position rather than an absolute speed.